* Each "dealloc" function frees raw memory that was allocated by the the
* "alloc" function. The memory's base and derived members might not have ever
* been initialized (but if "construct" returned successfully, then it has been
- * "destruct"ed already). The "dealloc" function is not allowed to fail. */
+ * "destruct"ed already). The "dealloc" function is not allowed to fail.
+ *
+ *
+ * Device Change Notification
+ * ==========================
+ *
+ * Minimally, implementations are required to report changes to netdev flags,
+ * features, ethernet address or carrier through connectivity_seq. Changes to
+ * other properties are allowed to cause notification through this interface,
+ * although implementations should try to avoid this. connectivity_seq_get()
+ * can be used to acquire a reference to the struct seq. The interface is
+ * described in detail in seq.h. */
struct netdev_class {
/* Type of netdevs in this class, e.g. "system", "tap", "gre", etc.
*
int (*get_queue_stats)(const struct netdev *netdev, unsigned int queue_id,
struct netdev_queue_stats *stats);
- /* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
- * ID, its configuration, and the 'aux' specified by the caller. The order
- * of iteration is unspecified, but (when successful) each queue is visited
- * exactly once.
- *
- * 'cb' will not modify or free the 'details' argument passed in. It may
- * delete or modify the queue passed in as its 'queue_id' argument. It may
- * modify but will not delete any other queue within 'netdev'. If 'cb'
- * adds new queues, then ->dump_queues is allowed to visit some queues
- * twice or not at all.
- */
- int (*dump_queues)(const struct netdev *netdev,
- void (*cb)(unsigned int queue_id,
- const struct smap *details,
- void *aux),
- void *aux);
+ /* Attempts to begin dumping the queues in 'netdev'. On success, returns 0
+ * and initializes '*statep' with any data needed for iteration. On
+ * failure, returns a positive errno value.
+ *
+ * May be NULL if 'netdev' does not support QoS at all. */
+ int (*queue_dump_start)(const struct netdev *netdev, void **statep);
+
+ /* Attempts to retrieve another queue from 'netdev' for 'state', which was
+ * initialized by a successful call to the 'queue_dump_start' function for
+ * 'netdev'. On success, stores a queue ID into '*queue_id' and fills
+ * 'details' with the configuration of the queue with that ID. Returns EOF
+ * if the last queue has been dumped, or a positive errno value on error.
+ * This function will not be called again once it returns nonzero once for
+ * a given iteration (but the 'queue_dump_done' function will be called
+ * afterward).
+ *
+ * The caller initializes and clears 'details' before calling this
+ * function. The caller takes ownership of the string key-values pairs
+ * added to 'details'.
+ *
+ * The returned contents of 'details' should be documented as valid for the
+ * given 'type' in the "other_config" column in the "Queue" table in
+ * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
+ *
+ * May be NULL if 'netdev' does not support QoS at all. */
+ int (*queue_dump_next)(const struct netdev *netdev, void *state,
+ unsigned int *queue_id, struct smap *details);
+
+ /* Releases resources from 'netdev' for 'state', which was initialized by a
+ * successful call to the 'queue_dump_start' function for 'netdev'.
+ *
+ * May be NULL if 'netdev' does not support QoS at all. */
+ int (*queue_dump_done)(const struct netdev *netdev, void *state);
/* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
* ID, its statistics, and the 'aux' specified by the caller. The order of
int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
enum netdev_flags on, enum netdev_flags *old_flags);
- /* Returns a sequence number which indicates changes in one of 'netdev''s
- * properties. The returned sequence number must be nonzero so that
- * callers have a value which they may use as a reset when tracking
- * 'netdev'.
- *
- * Minimally, the returned sequence number is required to change whenever
- * 'netdev''s flags, features, ethernet address, or carrier changes. The
- * returned sequence number is allowed to change even when 'netdev' doesn't
- * change, although implementations should try to avoid this. */
- unsigned int (*change_seq)(const struct netdev *netdev);
-
/* ## ------------------- ## */
/* ## netdev_rx Functions ## */
/* ## ------------------- ## */
void (*rx_destruct)(struct netdev_rx *);
void (*rx_dealloc)(struct netdev_rx *);
- /* Attempts to receive a packet from 'rx' into the 'size' bytes in
- * 'buffer'. If successful, returns the number of bytes in the received
- * packet, otherwise a negative errno value. Returns -EAGAIN immediately
- * if no packet is ready to be received.
+ /* Attempts to receive a packet from 'rx' into the tailroom of 'buffer',
+ * which should initially be empty. If successful, returns 0 and
+ * increments 'buffer->size' by the number of bytes in the received packet,
+ * otherwise a positive errno value. Returns EAGAIN immediately if no
+ * packet is ready to be received.
+ *
+ * Must return EMSGSIZE, and discard the packet, if the received packet
+ * is longer than 'ofpbuf_tailroom(buffer)'.
*
- * Must return -EMSGSIZE, and discard the packet, if the received packet
- * is longer than 'size' bytes.
+ * Implementations may make use of VLAN_HEADER_LEN bytes of tailroom to
+ * add a VLAN header which is obtained out-of-band to the packet. If
+ * this occurs then VLAN_HEADER_LEN bytes of tailroom will no longer be
+ * available for the packet, otherwise it may be used for the packet
+ * itself.
*
- * Specify NULL if this */
- int (*rx_recv)(struct netdev_rx *rx, void *buffer, size_t size);
+ * It is advised that the tailroom of 'buffer' should be
+ * VLAN_HEADER_LEN bytes longer than the MTU to allow space for an
+ * out-of-band VLAN header to be added to the packet.
+ *
+ * This function may be set to null if it would always return EOPNOTSUPP
+ * anyhow. */
+ int (*rx_recv)(struct netdev_rx *rx, struct ofpbuf *buffer);
/* Registers with the poll loop to wake up from the next call to
* poll_block() when a packet is ready to be received with netdev_rx_recv()